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Determine the solution set to the equation: 2sin^2x+cosx-2=0

  • Math -

    I will assume your domain is 0 --- 360

    2sin^2x+cosx-2=0
    2(1- cos^2x) + cosx - 2 = 0
    2 - 2cos^2x + cosx - 2 = 0
    2cos^2x - cosx = 0
    cosx(2cosx - 1) = 0
    cosx = 0 or cosx = 1/2
    x = 90º or 270º or x = 60º or x = 300º

    these can be easily converted to radians

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